Michelangelo had a sense for the materially significant as great as Giotto’s or Masaccio’s, but he possessed means of rendering, inherited from Donatello, Pollaiuolo, Verrocchio and Leonardo,—means that had been undreamt of by Giotto or even by Masaccio. Add to this that he saw clearly what before him had been felt only dimly, that there was no other such instrument for conveying material significance as the human nude. This fact is as closely dependent on the general conditions of realising objects as tactile values are on the psychology of sight.